src/main/java/org/yaml/snakeyaml/scanner/Constant.java

/**
 * Copyright (c) 2008-2010, http://www.snakeyaml.org
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.yaml.snakeyaml.scanner;

import java.util.Arrays;

public final class Constant {
    private final static String ALPHA_S = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-_";

    private final static String LINEBR_S = "\n\u0085\u2028\u2029";
    private final static String FULL_LINEBR_S = "\r" + LINEBR_S;
    private final static String NULL_OR_LINEBR_S = "\0" + FULL_LINEBR_S;
    private final static String NULL_BL_LINEBR_S = " " + NULL_OR_LINEBR_S;
    private final static String NULL_BL_T_LINEBR_S = "\t" + NULL_BL_LINEBR_S;
    private final static String NULL_BL_T_S = "\0 \t";
    private final static String URI_CHARS_S = ALPHA_S + "-;/?:@&=+$,_.!~*\'()[]%";

    public final static Constant LINEBR = new Constant(LINEBR_S);
    public final static Constant FULL_LINEBR = new Constant(FULL_LINEBR_S);
    public final static Constant NULL_OR_LINEBR = new Constant(NULL_OR_LINEBR_S);
    public final static Constant NULL_BL_LINEBR = new Constant(NULL_BL_LINEBR_S);
    public final static Constant NULL_BL_T_LINEBR = new Constant(NULL_BL_T_LINEBR_S);
    public final static Constant NULL_BL_T = new Constant(NULL_BL_T_S);
    public final static Constant URI_CHARS = new Constant(URI_CHARS_S);

    public final static Constant ALPHA = new Constant(ALPHA_S);

    private String content;
    boolean[] contains = new boolean[128];
    boolean noASCII = false;

    private Constant(String content) {
        Arrays.fill(contains, false);
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < content.length(); i++) {
            char ch = content.charAt(i);
            if (ch < 128)
                contains[ch] = true;
            else
                sb.append(ch);
        }
        if (sb.length() > 0) {
            noASCII = true;
            this.content = sb.toString();
        }
    }

    public boolean has(char ch) {
        return (ch < 128) ? contains[ch] : noASCII && content.indexOf(ch, 0) != -1;
    }

    public boolean hasNo(char ch) {
        return !has(ch);
    }

    public boolean has(char ch, String additional) {
        return has(ch) || additional.indexOf(ch, 0) != -1;
    }

    public boolean hasNo(char ch, String additional) {
        return !has(ch, additional);
    }
}